Blazing Moon causing havoc last night so the Gamma Cassiopeia region was probably not the best idea. However, managed to fit the M25C to the back of the Canon 200mm prime lens and then even managed to focus AND collimate it as well. For a short time I even had the magic 0.0" collimation as well - WOWSER. Managed to do a test-run of 10 x 10-minute subs with the lens set at f#4.5. Considering the greatest light polluter in the sky was up there doing its best to wreck things I am very happy with the result. As a major bonus (for me) I even captured a Carbon star HIP 4284.Greg